Within the field of rotary cutting tools used in milling operations, there are many examples of reversible cutting inserts being removably secured in a cutting body. In some instances, these cutting tools are configured to perform square shoulder milling operations.
U.S. Pat. No. 7,241,082 discloses a generally rectangular shaped double-sided indexable cutting insert having two major and two minor side surfaces connected to two opposing end surfaces, and a total of four major cutting edges. A primary ‘reversed’ relief surface adjacent each major cutting edge is inclined to a median plane of the cutting insert at an acute interior angle. The cutting insert is retained in the insert pocket of a milling cutter and configured to perform milling operations with a positive axial rake angle.
U.S. Pat. No. 7,455,483 discloses a trigon-shaped double-sided indexable cutting insert of ‘negative’ geometry having six edge surfaces connected to two opposing sides, and a total of six main cutting edges. The cutting insert is seated in the insert pocket of a milling tool and configured to cut perpendicular corners in a workpiece with a positive rake angle.
U.S. Pat. No. 7,604,441 discloses a square double-ended indexable cutting insert of ‘negative’ geometry having four side surfaces connected to two opposing end surfaces, and a total of eight primary cutting edges. The cutting insert is seated in the insert pocket of a milling cutter and configured to cut a true 90° shoulder in a workpiece with a positive axial rake angle. However, the depth of the shoulder is limited by the size of the insert and dependent on the length of the primary cutting edge.